3D-Printed biodegradable and multifunctional cranial device for bone repair and healing assessment

Critical-sized bone defects pose substantial clinical challenges, requiring both regenerative and diagnostic strategies for effective treatment. Here, we report a biodegradable, multifunctional cranial device based on three-dimensional printing. The device integrates a self-electrified scaffold based on a transient zinc-molybdenum battery and an impedance sensor for simultaneous electrical stimulation and continuous assessment of bone healing. The beneficial effects of electrical cues are attributed to elevated calcium ion influx, reactive oxygen species signaling, and up-regulated osteogenesis-related genes. In a rodent cranial defect model, the device promotes osteogenesis while enabling dynamic tracking of early tissue regeneration through impedance measurements. The increase in impedance is associated with enhanced collagen deposition and matrix mineralization. By uniting therapeutic stimulation with in situ monitoring, this work offers a platform for intelligent bone repair with broad potential in regenerative medicine.